XDrive-like service for non-Americans?

Any recommendations on shared storage space with access control? I've got people in China, Thailand, and Germany. I need to be able to grant varying levels of access to dirs for individual users. Cheap would be good, free better. Ease of use is essential, as some of my users have a tenuous grasp of computer concepts.

And yeah, XDrive would be perfect, but it looks like you have to be a US resident to get an AOL screen name.